The Underworld.
A broken half-moon hung high in the sky, casting a cold, eerie glow.
From the jagged gap in the moonlight, the waters of the River Styx fell straight down.
Beside the river, a sea of deep purple flowers stretched boundlessly.
The petals were as thin as soul-veils, interspersed with blue and pink blossoms. Though there was no wind, they trembled gently, creating ripples across the field.
One flower, one soul.
Suddenly, a slender, pale hand brushed through the flowers.
As her fingertips touched them, the petals vibrated slightly, as if responding to the girl's gentle touch.
The girl smiled serenely.
She sat in a wheelchair condensed from divine power.
She had short, light purple hair, and layers of bandages were wrapped around her body, hands, and legs.
Her bare feet rested on the wheelchair's footrests, making her look frail and weak.
The girl's eyes were tightly closed, her long eyelashes trembling slightly. The smile on her face hadn't faded, yet it couldn't hide the loneliness buried deep within.
"The flowers have bloomed."
"Sister."
The girl let out a sigh, her gentle whisper drifting across the River Styx.
"It has been so, so long."
The girl lowered her fingertips again, slowly sliding them over a flower. The petals trembled in response, releasing faint wisps of soul-light.
In that light, she saw a lingering shadow of a memory.
A woman, draped in tattered robes, holding a swaddled child, her back looking solitary as she walked across an endless wasteland.
The girl was none other than the Titan of Death, Thanatos—also known as Castorice's sister, Polyxia.
With a soft sigh, she withdrew her hand and slowly raised her head to look beyond the Underworld.
Though her eyes were closed, her vision could penetrate the Underworld and reach the other side.
Beyond the gates lay an endless shoal, shrouded in gray mist where the undead followed like shadows.
Day after day, they wandered, screaming silently, repeating the obsessions of their past lives—some in sorrow, some in anger, some in regret, and some in laughter.
They waded through the River Styx but could never reach the other side.
They were imprisoned forever in the gap between life and death.
"Sister, I... I look forward to the moment we meet, yet I am afraid to see you."
"This life of yours must have been very hard, hasn't it?"
When Polyxia spoke to Castorice, it showed she could see the outside world.
"I wait here alone, day after day, watching the desperate souls who are shut out by this lonely wasteland."
"Among them, I always hope to see your figure, yet I am afraid to recognize you."
This referred to the area outside the gates of the Underworld, including Styxia, which was washed by the waters of the River Styx.
She couldn't see any further.
Watching the aimlessly wandering souls, Polyxia clutched her chest tightly.
Through them, she seemed to see her sister's familiar figure struggling in the mortal world.
Isolated, misunderstood, hurt, yet always treating the world with gentleness.
She knew her sister had always been that way.
"Sis..."
"Eh—!?"
In the midst of reminiscing about the warmth of her past life, Polyxia suddenly froze, her fingertips curling up sharply.
Her "vision" swept rapidly through the crowd of souls.
Originally, it was just a habitual glance!
Just as she was about to withdraw her gaze, she discovered a familiar figure, a familiar silhouette.
Her vision came to an abrupt halt.
Tall, serene, gentle—even in the surging River Styx, she was as sharp as a blade.
It was her.
Her sister.
Polyxia's heart stopped for a moment.
In her excitement, she almost stood up from her wheelchair!
But...
The next scene left her with a head full of questions, and at the same time, it felt like she had been plunged into an ice cellar.
She saw her sister swimming toward the depths of the River Styx, following the dragon's remains all the way down.
Beside her was a man.
"Is that sister's boyfriend? But... they... shouldn't be able to touch each other, right?"
"Eh—"
"They... they're hugging? How is that possible?"
After she died and her remaining sanity returned to the Underworld, she understood everything.
As the death-half of Thanatos, she bore the fate of "Refusing Death," dying in the human world and returning to the Underworld.
And her sister, the life-half, bore the eternal curse of "Granting Death."
The palms of Death were split in two, and they could never touch each other again.
Logically, her sister shouldn't be able to touch anyone else.
But...
Brother-in-law was hugging sister, and sister was hugging brother-in-law. How was that possible?
"Be careful, sister—"
She saw countless souls in the River Styx swarming toward her sister.
They felt the sweetness of "Granting Death" and pounced like wolves, just to embrace death.
Although she knew her sister was fine, her heart still tightened for a moment.
Their hands, like the skeletal claws of tattered remains, reached out to grab her sister.
But in the next instant, brother-in-law's hand conjured circles of purple flames, shielding the two of them within and incinerating all the twisted souls that surged forward.
"Ah...?"
Polyxia's voice trembled, almost losing its tune.
It wasn't because of the strange sight of "lighting a fire" in the waters of the River Styx, but... in the sea of flowers before her, a cluster of small blue flowers suddenly bloomed.
"???"
Polyxia's eyes widened.
Every flower in the sea of flowers was planted by her own hand.
They were originally without birth or death, but in the first rain brought by the River Styx, they gained new life, carrying countless souls to flourish and grow.
When they withered and fell, turning into soil, they would rise into the sky as fine rain and fall back to the human world.
The same soul would cycle through reincarnation with different faces.
But!
After she "Refused Death," the "flowers" here would only decrease and never increase again.
These "souls" were all brought in during the first rain of the River Styx, and after her divine authority split, the River Styx no longer ushered souls in.
Flowers only decreased, never increased.
But now...
One, two, three?
Watching the "flowers" continuously blooming before her, Polyxia was stunned, her gaze turning toward her brother-in-law again.
Her brother-in-law could usher in souls?
"This..."
Wait!
What are they doing?
When her gaze turned back again, before she could even wake up from the shock of "ushering in souls," she saw an even more bone-chilling scene.
"Are they... digging up... my skull?"
Polyxia suddenly covered her small mouth, her closed eyes trembling.
Her small head was buzzing, as if countless silver needles were piercing through her skull.
She felt a sudden wave of dizziness hit her.
She saw brother-in-law and sister follow the River Styx all the way down until they reached the lightless depths, where they found her massive "skull."
Then brother-in-law pounced on it, hugged it, and with a sudden burst of strength in his arms—crack—he snapped her skull off.
"Ahem..."
Polyxia subconsciously raised her hand to touch her neck, feeling a bit of pain there.
It could be said that the giant dragon Pollux was her body.
Strictly speaking, it was the skeletal remains of a Titan.
Just like the massive Titan corpse in the deep sea of Phagousa.
After she molded her sister's soul into shape, she transformed into the giant dragon Pollux and used her last bit of strength to reach Styxia.
Unfortunately, after the divine authority split, she died the moment she reached the human world.
The dragon remains outside were her body, while the one in the Underworld was her "soul."
"This?"
What on earth is this?
Polyxia no longer knew what expression to make.
She saw brother-in-law in the River Styx, hugging her "skull" and swimming all the way to the shore, with sister following beside him.
She continuously killed the twisted souls that surged up.
Until they broke through the surface of the River Styx and jumped onto the shore.
...
"So big!?"
Watching the surging tides of the River Styx and the turbid waves hitting the sky, a massive pale dragon skull broke through the water. Vill-V, on the back of the World-Ender, widened her eyes in shock.
This was too big.
The tail was already larger than a high tower.
The skull was even more terrifyingly large.
"???"
Only then did Polyxia notice that there was another girl on the shore of the River Styx, and she was actually perched on a giant dragon!
That dragon's head emitted a world-ending aura that made even her feel a bit suffocated.
Moreover, the new flowers in the sea of flowers weren't all sent by her brother-in-law; more than half of them were because of this giant dragon.
"It... can actually usher in souls too?"
Polyxia murmured, her heart filled with overwhelming shock.
Laughs.
Don't forget, the World-Ender was a giant dragon that Ryuga had brought back to "New Life" from "Death" using the Flames of Creation.
It possessed both the power of death and the power to refuse death.
If the Titan of Death governed the rules of the Underworld on Amphoreus...
Then the World-Ender could tear those laws apart.
Born with both sides of life and death, it could be said that it was a natural Titan of Death.
Give it a Fire, and it could replace Thanatos.
"It's so big, how are we going to take it to the Underworld?"
Vill-V looked up, her neck feeling sore.
Laughs.
She couldn't even see where the edge was.
Vill-V felt like an ant standing next to an elephant's foot.
Ryuga chuckled: "Use this."
"Ah, this?"
Then, Polyxia was stunned again.
She saw brother-in-law take out a strange object and shine it on the dragon skull a few times.
In an instant, the skull shrank rapidly in her eyes.
In the blink of an eye, it turned into the size of a palm and was held in brother-in-law's hand.
Polyxia opened her mouth; this scene was too absurd and at the same time a bit awkward.
It felt as if she were being toyed with in brother-in-law's hand?
Sweat...
Castorice was the same, her eyes wide and round.
Then, Ryuga stuffed the shrunken dragon skull into his pocket.
Polyxia's mouth twitched, her heart full of speechlessness.
Just like that... he put it in his pocket?
"So, what about the other remains?"
Castorice finally came to her senses, looking up at the massive skeletal remains spanning the tower courtyard, feeling a bit curious.
So only the skull was needed? "The others aren't necessary. Get on, let's go."
As he spoke, Ryuga reached out and wrapped his arm around Castorice's slender waist, leaping onto the World-Ender's back.
Feeling the warmth of his palm through her clothes, a blush crept up Castorice's ears, and her breathing became light.
The giant dragon's wings slowly unfurled, and with a roar, it stirred the River Styx into a frenzy.
Next, he put Vill-V into the Wallpaper House, but opened a window so she could clearly see the scenes of the Underworld.
This way, she wouldn't have to worry about the sweet whispers of the Underworld eroding her mind.
After all, the current Vill-V would find it hard to resist.
The World-Ender beat its wings, tearing through the sky, carrying Ryuga and Castorice upward.
...
"Are—are they coming!?"
Polyxia suddenly became nervous. She frantically touched her face, her wheelchair spinning in circles on the ground in her panic.
She could perceive souls, but she couldn't reach the truth beyond the gates of the Underworld.
Her vision could only glimpse the banks of the River Styx.
She didn't know why brother-in-law could resist her sister's divine authority.
She even more so didn't know why brother-in-law and that dragon possessed the power of the Titan of Death.
She only knew that some kind of change seemed to have occurred outside.
And she knew her current expression management was a bit of a mess.
Her sister was coming, and she wasn't ready yet.
Whoosh—
Accompanied by a massive sound of wind, her smile instantly froze.
Then, the wind stopped.
The sea of flowers became still.
Even the flow of the River Styx seemed to hold its breath for a moment.
She saw the giant dragon carrying her sister descend from the sky, landing right in front of her.
In that moment of daze...
She seemed to see the scene of her carrying her sister against the current of the human world.
"So beautiful!"
Inside the Wallpaper House, Vill-V was frantically taking photos.
She never imagined that the Underworld of Amphoreus would be so beautiful; at first glance, one wouldn't even think this was the Underworld.
Only the broken moon in the sky, with the waters of the River Styx continuously flowing from it, looked a bit eerie.
"..."
Ryuga looked at the crescent moon in the sky, then at Castorice's sister Polyxia sitting in the wheelchair. So it really was like that?
He had long felt that the white and red moons in the sky were very strange.
And in Castorice's vision of touching death, she saw a black waterfall surging down from a gap in the sky.
When the alchemist awakened the dead dragon, he also said: "As above, so below; as below, so above."
Although these were alchemical terms from the Pharaoh's Emerald Tablet...
And when parting with Trailblazer and flying to the Underworld on the dead dragon, they also flew toward the moon.
Additionally, he remembered that the broken moon in the Underworld was where the River Styx flowed from.
Connecting this to the "moon" in the land of iron sand in Honkai Impact 3rd...
Ryuga understood.
"The Underworld... really is like the legends say, like the flower field we used to tend."
Castorice slowly scanned the boundless sea of Equinox flowers, murmuring softly.
Then she jumped down from the dragon's back, looking at her sister in the wheelchair, her eyes shimmering with gentle ripples.
When a thousand words gathered at her lips, in the end, there was only one greeting.
"Right, sister?"
"Yes, long time no see, sister." Polyxia tilted her head slightly and smiled serenely. "Do you... remember me?"
Too many bizarre things had happened today.
First, a man and a dragon with the power of the Titan of Death, unafraid of the erosion of her sister's power of death.
And then, her sister returning with memories of her past life.
This wasn't right.
"I don't have those memories. Your story was all told to me by the Lord Demon God."
Hearing this, Castorice shook her head.
Then she stepped aside, gesturing toward Ryuga on the dragon's back.
Demon God?
Polyxia operated her wheelchair, gliding forward a few steps.
"Hello, brother-in-law. I am the Titan of Death, Thanatos. My name in my past life was Polyxia."
The atmosphere froze for an instant.
Inside the Wallpaper House, Vill-V was stunned.
Bro-brother-in-law?!
Ryuga was also stunned for a moment, his pupils shrinking slightly, and then his eyes suddenly lit up.
As expected of a sister-in-law, she really has good taste.
"Brother-in-law?"
Sizzle—!
Castorice's face instantly turned beet red, so red it looked like it might drip blood.
She abruptly turned her head away, her eyes darting around, not daring to look at her sister.
She felt her ears burning and her heart pounding like a drum, like a startled deer.
Her small hands were constantly rubbing together, not knowing where to put them, and finally, she just twisted the corner of her skirt.
"You, you you you what are you say..."
Castorice whispered in a tiny voice, so quiet it was like the buzzing of a mosquito; even she couldn't hear herself clearly.
"Hello, little Polyxia. That's right, I am your brother-in-law."
Ryuga jumped down from the dragon's back, strode forward, and with one arm, pulled Castorice's slender waist into his embrace.
Castorice's body stiffened, her face turning even redder, and she stammered: "I I I I..."
"Is sister still shy? Earlier, I already saw the scene of you two hugging; sister, you didn't refuse at all."
Polyxia suddenly covered her mouth and let out a soft laugh.
Was that me not refusing?
That was him being too fast, I couldn't react in time, okay!
Castorice weakly complained in her heart.
"It's our first meeting, and I came in a hurry, so your brother-in-law didn't bring any decent gifts."
Ryuga spoke solemnly, then reached into his pocket and took out the "dragon skull."
"Here—"
"I brought your skull."
The atmosphere froze once again.
Polyxia's expression froze on the spot, her pupils vibrating slightly, and her mouth twitched.
She stared at the skull for a moment, then looked up at Ryuga, as if confirming she hadn't misheard.
Look at what you're saying!
Who brings someone's skull as a first-meeting gift?
A congratulatory gift?
A declaration of war?
The girl opened her mouth, not knowing what to say.
"Sister-in-law, watch your brother-in-law perform a magic trick for you."
Ryuga blinked.
He gently placed the dragon skull on the ground, then took out a pink test tube and dripped a few drops of potion on it.
Instantly, foam surged.
In the blink of an eye, a complete skeletal remains of a dragon appeared in the Underworld.
To be continued…